<html>
<head>
    <meta charset="UTF-8">
    <title>test ajax</title>
    <script>
        function showHint(str)
        {
            if (str.length==0)
            {
                document.getElementById("txtHint").innerHTML="";
                return;
            }
            if (window.XMLHttpRequest)
            {
                // IE7+, Firefox, Chrome, Opera, Safari 浏览器执行的代码
                xmlhttp=new XMLHttpRequest();
            }
            else
            {
                //IE6, IE5 浏览器执行的代码
                xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
            }
            xmlhttp.onreadystatechange=function()
            {
                if (xmlhttp.readyState==4 && xmlhttp.status==200)
                {
                    document.getElementById("txtHint").innerHTML=xmlhttp.responseText;
                }
            };
            xmlhttp.open("GET","gethint.php?q="+str,true);
            xmlhttp.send();
        }
    </script>
</head>
<body>

<p><b>在输入框中输入一个姓名:</b></p>
<form>
    姓名: <input type="text" onkeyup="showHint(this.value)">
</form>
<p>返回值: <span id="txtHint"></span></p>

</body>
</html>
